2 GastroenteritisGastroenteritis is a nonspecific term for a variety of pathologic states of the gastrointestinal tract.The primary manifestation is diarrhea, but it may be accompanied by nausea, vomiting, and abdominal pain.A universal definition of diarrhea does not exist, although patients seem to have no difficulty defining their own situation.

3 GastroenteritisAlthough most definitions center around the frequency, consistency, and water content of stools, the author prefers the definition that diarrheal stools take the shape of their container.

4 GastroenteritisSeverity of illness may vary from mild and inconvenient to severe and life threatening.Appropriate management requires extensive history and assessment and appropriate general supportive and, often, etiology-specific treatment.Diarrhea associated with nausea and vomiting is referred to as gastroenteritis.

6 Diarrhea is……..A symptom characterized by an abnormal increase in stool frequency or liquidityAcute diarrhea is usually self limiting and lasts hours, sometimes up to 7 daysChronic diarrhea lasts more than 4 weeks, should seek medical care

7 Global Problem4.6 million children less than 5 years of age die of diarrheal diseases.Diarrhea accounts for 19% of all deaths among children ages 0-4.Eighty-five percent of diarrheal deaths occur in the first year of life.World Health Organization WHO Fact Sheet: Reducing Mortality from Major Childhood Killer Diseases. Fact Sheet Number 180.Centers for Disease Control and Prevention Diarrhea: The Management of Acute Diarrhea in Children: Oral Rehydratioin, Maintenance, and Nutritional Therapy.Graph.

8 OUTBREAKSJuly 1998: E coli 0157:H7 infection outbreak from contaminated water supply in Wyoming, more than 60 infectedJuly 1995: 77 cases of cryptosporidiosis at a day camp in Florida, most likely secondary to water hose contaminationAugust-September 1999: E coli 0157:H7 infections secondary to contaminated well water in Washington County Fair (New York)

9 OUTBREAKSThree to five billion cases of acute diarrhea occur yearly, and it is the leading cause of death in many underdeveloped countries.Approximately 30-50% of visitors to developing countries will develop, and perhaps return with, diarrhea.

10 Age Gastroenteritis may occur at any age.Morbidity and mortality are much higher in the very young and the very old.

14 Behavioral FactorsFailure to breast-feed exclusively for the first 4-6 months of lifeFailure to continue breast-feeding until one year of ageUsing infant bottlesStoring food at room temperatureContaminated drinking waterFailure to wash handsFailure to dispose of feces hygienicallyClaeson, M., & Merson, M Global progress in the control of diarrheal diseases. Pediatric Infectious Diseases Journal, 9:

17 DiarrheaThe passing of 3 or more watery or loose stools in a 24-hour period.Three types: acute waterypersistentdysenteryWorld Health Organization The Epidemiology and Etiology of Diarrhea.World Health Organization WHO Fact Sheet: Reducing Mortality from Major Childhood Killer Diseases. Fact Sheet Number 180.

18 Diarrheal illnesses also may be classifiedOsmotic, due to an increase in the osmotic load presented to the intestinal lumen, either through excessive intake or diminished absorptionInflammatory (or mucosal), when the mucosal lining of the intestine is inflamed.Secretory, when increased secretory activity occursMotile, caused by intestinal motility disorders

21 Etiology of diarrhea Viral (50-70%)The Norwalk virus is the leading cause of viral gastroenteritis in the United States. Norwalk virus belongs to the species of Noroviruses (formerly known as Norwalk-like viruses). Noroviruses, along with the Sapoviruses (formerly known as Sapporo-like viruses) are members of the Caliciviridae family of viruses.Caliciviruses: Various caliciviruses, other than Norwalk, are likely responsible for many out breaks of previously unidentified viral gastroenteritis.Rotavirus: A leading cause of gastroenteritis in children, but can also be found in adults. May cause severe dehydration.AdenovirusParvovirusAstrovirusCoronavirusPestivirusTorovirus

27 Viral gastroenteritis80-85% of episodes of acute diarrhea are caused by virusesVirus transmitted by contaminated food or waterClinical features include 12-48hr incubation period followed by vomiting, watery diarrhea and low grade feverIllness lasts 5-8 days, treatment is fluid and electrolyte therapy

31 Antibiotic associated diarrheaFrequency of diarrhea is largely dependent on the extent to which the drug disrupts the normal intestinal floraAbx that have broad spectrum activity against aerobes and anaerobes can produce diarrheaAAD may be caused by an overgrowth of abx resistant bacteria, fungi, or toxin producing C.difficileDiarrhea caused by C.difficile is usually watery and greenish-mucoidThere are no nonprescription treatments for eradicating C.difficile

32 AIDS Associated DiarrheaPatients with AIDS or HIV are known to be susceptible to intestinal infections that produce diarrheaThese patients should not self-manage their diarrhea, they should see their physician

33 Food-Induced DiarrheaFood intolerance can provoke diarrheaThe enzyme lactase hydrolyzes disaccharides into monosaccharidesWhen you lack the lactase enzyme, disaccharides can not be hydolyzed to monosaccharidesDisaccharides pool in lumen causing an osmotic imbalance which draws fluid into the lumen and causes diarrhea

42 Fluid and Electrolyte ReplacementNot more than mEq/L of Na for rehydrationNot more than mEq of Na for maintenanceCarb to Na ratio should be 2:1Important in children and infantsAll patients should rehydrate and maintain during diarrheal episode

43 Loperamide Good for treatment of traveler’s diarrhea and IBDWorks by slowing intestinal motilityUse 4mg initially, then 2mg after each loose stool but do not exceed 16mg/day (8 tablets)Do not use in children <6 years old use electrolyte tx instead

44 Adverse Reactions Can cause occasional dizziness and constipationMay worsen effects of invasive or inflammatory bacterial infection should not use for food borne illnessMay cause toxic megacolon in ABX induced diarrhea DO NOT use for ABX associated diarrhea - refer to physicianIn children less than 6 years old

45 Absorbents Include attapulgite, kaolin, pectinDo not recommend because of decreased absorption of other drugs

46 Polycarbophil Used for non-specific diarrheaBulk laxative that is also effective in treating diarrhea (can also treat constipation)Can absorb up to 60X weight in waterUse 2 (500mg) tablets 4 times daily or after each loose stool (up to 6g a day)

48 Bismuth Subsalicylate BSSUsed for non-specific diarrhea, indigestion, tx and prevention of traveler’s diarrhea, as adjuvant to ABX for treating H.pylori peptic ulcer diseaseReported to have an antisecretory mechanism to bind bacterial toxins, and to have anti-inflammatory and antibacterial propertiesTake 2 (262mg) tablets every hour up to 16 tablets a dayNot recommended for children <2 years old

49 Adverse ReactionsMay reach toxic levels of salicylate if patients are taking aspirin or other salicylate containing drugsPatients sensitive to salicylates should not useBlackened stool and tongue may occur - harmless

54 Complications of DiarrheaAcute diarrhea may cause severe dehydration and electrolyte imbalanceInfants, young children, and the elderly are most at risk for dehydrationChildren less than 2 yrs of age often have complications that require hospitalization

65 WORLD HEALTH ORGANIZATIONYou might be facing an outbreak very soon ifYou have seen an unusual number of acute diarrhoeal cases this week and the patients have the following points in common:they have similar clinical symptoms (watery or bloody diarrhoea)they are living in the same area or locationthey have eaten the same food (at a burial ceremony for example)they are sharing the same water sourcethere is an outbreak in the neighbouring community

66 WORLD HEALTH ORGANIZATIONYou have seen an adult suffering from acute watery diarrhoea with severe dehydration and vomitingIf you have some statistical information from previous years or weeks verify if the actual increase of cases is unusual over the same period of time.

67 WHAT DO I HAVE TO DO WHEN I SUSPECT AN OUTBREAK?1. Inform and ask for help2. Protect the community3. Treat the patients

83 Mortality/MorbidityEstimates for mortality and morbidity vary widely. In the United States, 210,000 pediatric hospitalizations occur yearly with as many as 10,000 deaths.Internationally, mortality rate is 5-10 million deaths each year.